Electric boiler



H. E. COHEN.

ELECTRIC BOILER.

APPLICATION HLED MAR. 4, 192'2.

Pan'a June 27, 1922.

2 SHEETS-SHEET 1.

HI Ill' 66 /NVENTo/e A TTORNEYS H. E. COHEN.

ELECTRIC BOILER.

APPLICATION HLED MAR. 4, 1922.

Patented June 27, 1922.

2 SHEETS-SHEET 2.

w' A Trak/v5 Ys UNITED s'rATEs PATENT OFFICE.

HYMAN E. COHEN; OF SYRACUSE, NEW YORK.

ELECTRIC BOILER.

Specification of Letters Patent.

Patented June 27, 1922.

Application fiied March 4, 1922. serial No. 540,968.

generator disclosed in my copending ap? plication Serial. NumberJ;1(3,899, filed October 12, 1920; and has special reference to theprovision of a boiler of this nature which may be operated witli amaximum of surety, safety and facility.

In the steam generator forming the subject matter of my above mentionedcopending application one or more electrical heating elements in theform of resistance tubes is or are arranged in a boiler and disposed ytherein with an end or the ends of the tube 'or tubesl exposed above thewater level, the

said tubes when electrically heated, as by passing a currenttherethrough, etfecting the segregation of water within the tube, theheating of the said segregated water and the expulsion of the same fromthe top end 'of the tube in the form of generated steam. These tubes inone form of my invention are arranged to be fioated in the boiler forfollowing the changing liquid level therein to the end of maintainingthe upper ends of the tubes exposed above the water level a Constantpredetermined amount. A prime desideratum of my present inventioiicomprehends the provision of a boiler` construction in which theelectrical resistance tubes are floated in a 'nanner to render theoperation of the sanie in practice safe, dependable and secure.

I have found after considerable experimentation that in order to obtainan eflicient floating construction in the steam boiler, which is usuallysubjected to considerable pressure during steam generation, that suchfactors as the character of the fioat, the mounting of the float andmovement of the same in the boiler casing are considerations of primeimportance. It is very desirable, for example, that the fioat be freelymovablle in the boiler casing without let or hindrance so that the riseand fall of the fioat may be assured during changeslin the liquid levelof the boiler. Moreover, the construction of the float should be such asto withstand the heavy pressure to which it is subjected in practice.Furthermore, the electrical resistance elements must be so mounted o nthe float and associated With the boiler casing as to prevent the samelfrom making contact with the boiler casing to minimize groundingtroubles and' also to prevent the same from moving transversely in thecasing to reduce the liability or tendencyof grounding or largelymodifying the .resistance between the said electrical heatingelements-and the boiler casing. A principal object of the presentinvention therefore compreheiids the provision of a construction 'inwhich the float and the tubular elements thereon are eflicientlysupported within the casing and movable there- 1n to prevent undesirablebinding and jamniing of the parts and .to permit the free rise and fallof the float with the construction such as to minimize or .prevent anygrounding tendency of the electrical heatmg elements.

Another important desideratum of my present invention comprehends aconstruction of th'e type referred to in which the electrical elementsare protected against burn outs and in which needlessconsumption ofenergy is prevented when the water in tlhe boiler falls'below .aipredetermined eve I have found it hglily desirable where an absolutelysafe and dependable boiler is desired to provide au automatic cut-outmeans operable by movement of the float in the boiler, the constructionand arrangement bemg such that when the tloat following the water levelfalls below a predetermined height, the Circuit to the electricalheating elements is opened or cut out to prevent the wastage of currentand to prevent the burning out of' the electrical heating elements.

Atfurther principal object 'of the invention tliei'efore comprehends theprovision of a cutout means of this nature which is eflicieutlyassociated in a simple manner with the floating apparatus.

To tlie accomplishment of the foregoing and such other objects as mayhereinafter appear, myinvention consists in the eleinents andtheirrelation one to the other, as hereinafter particularly describedl andsought to be defined in the claims, reference being had to boilershowing the fioating equipmenttherein, and

F igu're 2 .is a perspective and diagrammatic view thereof showing, thefloating equipment removed from the boiler casing and the controlcircuits therefor.

Referring now more in detail to the drawings, the electric boiler of myinvention com'- prises the preferably cylindrical casing orshelly10,lthe said casing being provided With the closure 11 adapted tobe attached to the casing structure as bytbeing bolted to a top flange12 of the boiler casing as by means' of the spacedly arranged bolts 13,the suitable gasket 14 being interposed between the closure and the4casing flange for obtaining an effective seal between these parts.Connected to the bottom of the casing Shell 10 there is providedthewater inlet piping 15 and connected' to lthe side wall of the boilercasing 10 adjacent its top there is provided the steam outlet piping,16. The boiler may be further providedwith the usual water gauge 17'and the pressure gauge 18'. The casing.

or Shell 10 is intended for the recept-ionof a suitable supply of waterand for. heating this water for steam generation I provide a pluralityof electrical .resistance elements in the form of carbon tubes, asdisclosed in m above mentioned copending application, 'the said carbontubes functioning to segregate' portions of the water in theboiler'shell and to heat the same substantially instantly for generationof steam. The resistance tubes preferably comprise a plurality oftubular elements 17 .arranged in series and connected by means'of aplurality of connectors .18, these tubular elements being connected toany source of electrical supply, one end of the series of tubes being.to this end electrically connected by means of a conductor 19,

to a binding post 20 attached to the boiler closure 11l and suitablyinsulated there-from, the other terminal of the series of tubes 17 beingconnected by ;means of a conductor 21 to a second bindin post 22.carried by the boiler closure' 11 an suitably insulated thereo from,thebindingposts 20 and 22 being intended for connection to a suitablesource of supply, as wil'be made clearer hereinafter. Upon ener izationor closing of the circuit to the heating units 17 ,the water segregated.

thereby is instantly heated and transformed into steam which issues fromthe top ends of the tubes in a continuous lfountain formation. The tubes17 are preferablyarranged within the boiler casing with the top endsthereof exposed above the Water level 'to the 'end of 'efectingefficient steam generation,'

and `where a Constant characteristic of steam is desired, itispreferred-to' maintain the exposed ends of the tubes in constant a'ndpredetermined relation With respect to the water level and for thispurpose these tubes are floated within the boiler to follow the changingliquid level therein.f y

- As heretofore stated, a rincipal object of my present inventionre atesto' the. provision of a boiler 'construction' in which the fioatedheating elements-are arra' ed "and mounted for eflicie'nt movement an'operation in the boiler, the floatingl equipment being adapted to riseand fall with the 'changing. liquid level with facility and surety. F orthe purpose of withstanding the high pressures attainable in -the boilerduring steam generation I have found it very 'desirable to provide thehollow substantially ball. shaped metallic float 23 and lto the float Iattach the resistance elements 17, thelatter being preferably arrangedcircumferentially or peripherally on the said float. A' very convenientmeans of attaching the resistance elements to the float comprises theprovision of a resilient and insulating sheath such as a rubber covering24 stretched over the flattenedside walls 25 of the float, the series ofy semi-cifrcular sections hinged together by means-of' the hingingelement` 27, the other ends of these semi-circular Sections beingadapted to be drawn together by means of a clamp 28, the provision ofthis means elffecting' a secure attachment of the tubes 17 on the float23. For obtaining 'a float which will readily respond and rise andfallwith the changing liquid level in theboiler while minimizing groundingtendencies, I have found it very suitable to provide a rectilinearguiding means for the float, the guiding -means conveniently comprisinga preferably vhollow stem 29 carried by the boiler closure 11 as by'being threadedly received by 'a plug 30 which in turn is threadedlyattached to the boiler closure-11 as at 31, the said hollow stem 29slidably receiving the float 23 and the` heating elements carriedthereby, the said float 23 beingl referably provided with acentraljjsleeve-liie integral portion 32 of a diameter to'be freelyreceived by the hollow -stem 29. vThe Stein 29 is preferably arrangedVcentrally of the cylindrical shell 10 andthe float and its attachedresistance tubes are thus preferably movable centrally 'of .the boiler.'With theprovision o f this construction the floatingequipment isefficiently ided for movement within the boiler casing for obtaining adependable operation thereof'.

' For the urpose of obtaining a safe and fool-proc i construction toprevent' the needless consumption of energy and to prevent the burningout of the heatin'g elements When thie Water in the boiler is or fallsbelow a predetermined level, I have found it desirable to provide meansfor controlling the energiz'ation of the Circuit to the heating elementsdepending upon the position of the floating equipment in the boiler.Referring now toFigure 2 of the drawingsl, the Circuit totheheatingelements may.l comprise the Conductors 33 and34 'Connecting the bindingposts and 22 through fuses 35 and 36, if desired, to a main controlswitch 37, the conductor 33 being connected through the i bar 38 of'the'said switch to line 39 leading to a source of supply, the conducior34' being connected through the other bar 40 of the switch to the otherline 41 leading to the source of supply. The switch 37 is normallymaintained in open position and to this end this switch is springControlled, a .spring 42 being provided anchored to the transverseinsulating bar 43 of the switch 37 for maintaining' the said 'switch inthe normaliy open position as indicated in full lines in figure 2 of the-drawings F or controlling the Circuit to the heating elements, theswitch 37 is controlled so that operability of the said switch isprevented under the ab-' normal boilerconditions presented when theliquid therein falls .below a predetermined' level., I f

For controlling the V'switch 37 to control the Operability thereof,there is preferably provided a second Circuit Controlled by thev'movement andthe position of the fioating equi ment within the1b oi1er.Still referring to igure 2, this circult includes a solenoid orelectro-magnet 44, one terminal of which is connected to the conductor,34 by means of the conductor 45, the other terminal of which isconnected by means of a conductor 46 to a third bindingpost 47 carriedby the boiler closure. 11 and suitably insulated therefrom, the bindingpost 47 being in turn connected to a vcutout switch generally designatedas 48 adapted for cooperative association with the binding post 20, aswill be described' presently, for closing the Circuit.

to the cond-uctor 33. A This Circuit including the-solenoid 44 istherefore arranged in parallel 'with' thevheating elements acrossthe;lines 33 and 34, energlzation or deenergization of the solenoid 44lbeing therefore under .the control of the main switch 37. The solenoid44` is arranged for Operating an larmatui'e looking element 49, thelatter being pivotally mounted as at 50 and normally urged toinoperative position by means of a i lspringl anchored the-reto. Thearmature 49 may be suitably notchedas at 52 to cooperate with a. lockinpin or st'ud 53- formiing. part .of or attac ed to the switch 37.

ytion for unlocking the switch 37 and the .ment with a stationarycontact arm 55, the

With the provision of this construction it will be evident that uponenel'gization of electro-magnet or solenoid 44 the armature lookingelement`49 will be moved to Cooperate with the locking stud 53 for thepurpose of looking the switch 37 in closed position in the event thatthe said switch is moved to the said closed position, -the switch beingmaintained in closed position during continued energization of themagnet' 44. It will be further apparent that in the operation of theboiler, if the magnet 44 is de-l ene'rgized, the lock armature 49 `willbe' moved by the spring 51 to inoperative posispring 42 will move thesaid switch 37 to open position for opening the circuit to the heatingelements..` v

For efiiecting the desired'controi of the armature 49 by theelectro-magnet 44, the. cut-out switch generally designated as'48hereinbefore mentioned is provided. The switch 48 comprises a movableswitch orfcontact arm 54 movable into and out of engagemovable arm 54being rockabiy mounted about a pivot 56 provided in an upstandingbearing 57 formed preferabiy integrally with a bracket 58, which isconnected mechanically and electrically to the binding. post 47, thestationary contact arm.55 being in turn attached 'for electricalconnection to the binding post 20. For movin'g'the contact arm 54 intoandout of operative engagement with the contact arm 5'5 there isprovided a rod 59 slidably movable in` an apertured boss 60 forming partof the bracket 58 and connecting the rod 59 and the switch arm 54 thereis provided a tension spring 61, one end ofv which is anchored to theend of. the arm 54, the other end of which is anchored to the rod 59, aswill be Clear from a consideration of Figures 1 and 2 of the drawings.The rod 59 is adapted for sliding movement in the boss'bearing 60 and.V110

when the rod is moved to its uppermost position the spring 61 will exerttension upon the arm 54 for moving the same intothe contacting positionas shown in Figure 1 of the drawings. When the rod 56 is moved todescended position as indicated in dotted lines in Figure 1 and as shownin Figure' 2 of the drawings, the spring 61 exerts tension upon the arm54 for snapping the Same' out of contacting position, thus opening thecircuit to the electro-magnet 44. The position, therefore, of the rod 59controls the operability of the magnet 4-4 and therefore the operabilityof the main switch 37.

within the hollow stem 29, an insulating rod or bar 63 being providedfor connecting the rod 59 to the rod 62, one end of the bar 63 beingadjustably attached to the rod l59 as by means of the adj ustablelooking nuts 64, the other 'end of the insulating bar 63 being attachedto the rod 62 as by receiving an outwardly turned portion G5 thereof.The rod 62 is provided at its bottoni end with a stop disk 66 which maybe adjusted on the rod 62 by means of the adjustable lock nuts 67, theadjustment being provided for varying the region in which the cut-outswitch S is to be operated by the fioating equipment. With the provisionof this construction it will be seen that as the fioating equipmentdescends with the Afall in the liquid level the bottom portion of thefioat 23 when the fioat reaches the position as indicated in dottedlines in Figure 1 of the drawings, will engage the 'stop disk 66 andwill move the rod 62 in the hollow stem 9:9, a suitable slot 68 beingprovided in the side wall ofthc stem for permitting this motion,movement of the rod '82 effecting, aswill be ohvious, the descent of therod 59 and the movement of the switch arm 54 to open position asindicated in dotted lines in Figure 1. ith the parts arranged in thismanner the switch will be automatically opened and'when the switch 37 ismanually closed the said switch will not be maintained closed under thisabnormal boiler condition. lt will be further apparent that when asupply of water is admitted to the boiler casing 10 the i'ioatingequipment will rise to the position shown in Figure 1 of the drawings,and in rising to the desired level the upper portion of the float 23will enga'ge the insulating bar 63 for moving the contact arm 54; toclose the circuit Controlled thereby. When the tank orboiler shell isthus filled to the desired height, the electro-magnet 4a is conditioned,for energization when the switch 37 is closed, the lo'cking means forthe said switch being thus rendered operable. The stop disk 66, besidesfunctionlng for being engaged by the fioat 23 for Operating the switch48, also functions as a stop element to prevent movement of the fioat 23from the stem 29, this construction providing the attachment oflthecomplete float-ing equipment and the cut-out switch to the boilerclosure 11, removal of the boiler closure as shown in Figure 2 of theldrawings being effective for removing the entire floating equipment andassociated parts for purposes of inspection or I'epalr.

The operation and use of Iny electric boiler will, in the main, beapparent from the above detailed description thereof.. It. will. beapparent that when the boiler is suitably supplied with water to thedesired height, the main control switch 37 when manually closed Will bemaintained closed for connecting the. heating tubes `17 to a source ofcurrent supply, heating of thetubes etfecting the generation of`steam inthe chamber above the water supply, the steam moving through the Outlet16 for use in other apparatus. As the liquid supply becomes exhaustedthe ioating tubes 17 move downwardly in the boiler casing suitablyguided to obtain facile operation and to eliminate grounding tendencies,a predetermined amount of the upper ends of the tubes being maintainedabove the water level. lVhen the water level falls below a`predetermined minimum the cut-out switch 48 will be operated to(leenergize the inagnet 4A for unlocking the switch 37 and for effectingthe opening of the circuit to the heating elements, a safe anddependable operation being thereby provided.

lfhile have shown my device in the preferred form will be obvious thatmany changes and modiications may be made in the structure disclosedwithout departing from the spirit of the invention7 defined in llowingclaims.

In an electric boiler., a boiler casing, a fioat movable therein and:idapted to follow the changing liquid level in the boiler, heatlngelements carried by the fioat and means for guiding the fioat in itsmovement in the boiler, the said means comprising a stem slida-blyreceiving the Said fioat.

:nan electric boiler, a boiler casing, a

1' hollow metallic fioat movable therein and adap'fd to follow thechanging liquid level in the boiler, electrical heating elements'insulatably carried by the fioat and means for guiding the fioat in itsmovement in the boiler, the said means comprising a stem connected tothe boiler' casing, the said stem slidably receiving the said fioat.

3. In an electric boiler and steam generator, al casing, a fioat movabletherein and adapted to follow the changing liquid level in the boiler,tubu'lar electrical heating elements carried by the fioat' and movabletherewith, the arrangement being such that the upper ends of the tubularelements are exposed above the water level and means for guiding thefioat in its movement in the boiler with the said tubeends maintainedabove the water level, the said means comprising a centrally locatedstationarily mounted stem receiving the said fioat for free slidablemovement thereon.

4. lin an electric boiler, a vboiler casing including a boiler closuretherefor, a-fioat movable within the casing and adapted to follow thechanging liquid level in the boiler, heating elements carried by thefioat and means for guiding the fioat in its movenient in the boiler,the said means comprising a stem carried by the said closure andsiidably receiving the said fioat and means i stem', the constructionbeing-such that the float and the stem are removable as a unit with theboiler closure.

5. In an electric boiler, a boiler closure, a'

stem carried thereby, a float slidably movable on the stem and heatingelements carried by the float.

6. In an electric boiler, a boiler closure, a stem carried thereby andlocated centrally thereof, a hollow metallic float slidably movable onthe said Istem and a plurality of electrical heating tubes carriedby`th'e float for movement therewith. v

7. In an electric boiler, a heating apparatus adapted for following thechanging liquid level in the boiler, the'said heating apparatuscomprising a hollowisubstantially ball shape'd float and a series oftubular electrical resistance elements mounted on the float and arrangedvcircumferentially thereon.

float, a plurality of tubular electrical resistance elements carried bvthe float and arranged peripherally thereof and means for supporting thevtubular elements on the float,

the said means comprising a resilient sheathl interposed between thefloat and the heating elements and a peripheral clamping band arrangedexternally to the-heating elements for clamping the same in position onthe float.

9. In an electric boiler, a boiler casing, a float movable therein andadapted to follow the changing liquid level in the said boiler, heatingelements carried by the float, an electricalcircuit therefor andprovisions for controlling the said circuit to the heating velementsincluding switch means controlled 'by the movement of the float.

10. In an electric boiler, a boiler casing, a' float movable therein andadapted'to follow the changing liquid level: in v'the' said boiler,heating elements carried, by the'float, an electrical circuit thereforand provisionsv for controlling the said circuit to the heating elementscontrolled by the movementof the float.

11. In an electric boiler, a boiler casing, a float movable therein andadapted to follow the changing liquid level in the boiler, tubularelectrical' resistance heating elements carried by the float adapted forconnection to an electrical circuit and provisions for controlling thesaid 'circuit to' thefjheating elements'controlledby the movement of thesaid float. J i

12. In an electric boiler, a boiler` closure,

a float carried 'by the boiler closure and adapted for movement within"the boiler for the changing liquid level therein,

following heating-'e ements carried by the float, anelectrcalclr'cuittherefor and provisions'carried by the said closure forcontrolling the said circuit to the heating elements, the saidprovisions being controlled by movement of the said float.

13. In an electric boiler, a float movable in the boiler and adapted tofollow the changing liquid level therein, electrical heating elementscarried by the float, a circuit therefor, a cut-out switch movable forcontrolling the said circuit to theI heating elements, the Said switchbeing operated by movement of the float in the boiler.

. 14. In an electric boiler, a boiler casing, a floatmovable therein andadapted to follow the changing liquid level in the boiler, heatingelements carried by the float, means for guiding the float in itsmovement in the boiler comprising a stem slidably receiving the saidfloat, an electrical circuit for the heating elements, switch means forcontrolling the said circuitvand provisions for operating the saidswitch means, the said provisions being also movable on the stem andcontrolled by the movement of the said float.

15. In an electric boiler, a boiler closure, a float movable within theboiler and adapted to follow the changing liquid level therein, heatingelements carried by the`float, means for guiding the float in itsmovement in the boiler comprising a stem carried by the said closure andslidably receiving the said float, an electrical circuit for the heatforthe heating elements, lswitch provisions.

for controlling the said circuit and means movable onthe stem forvOperating the said provisions, the said means being movable to twopositions on the sal stem, the construction beingsuch that when'thefloatis moved to a predetermined upper level the said means will bemoved to one position and when the float -is moved to a predeterminedlower level the said means will be moved to its other position.

17. In an electric boiler, a boiler casin a float movable therein andadapted to ollow the changing liquid level in the'boiler, electricalheating elements carried by the float, a circuit therefor, a controlswitch in said circuit and means for preventing operability of the. saidcontrolswitch under abnormal boiler'conditiona? the said means includingprovisions ai'renged within the css,-

ing and Controlled by the position of the said float.

18. In an electric boiler, a boiler casing, a float movable therein andadapted to follow the changing liquid level in the boiler, electricalheating elements carried by the float, a Circuit therefor, a controlswitch in said Circuit and means 'for preventing operability of the saidcontrol switch under abnormal boiler conditions, the said meansincluding a second switch arranged within the Casing and controlled bythe position of the said float.

'19. In an electric boiler, a boiler casing, a. float movable thereinand adapted to follow the changing liquid level in the boiler, anelectrical Circuit, a switch in said circuit andmeans for preventingoperation of the said switch under abnormal boilei` Conditions, the saidmeans including provisions arranged within the casing and Controlled bythe position of the said float.

20. In an electric boiler, a boiler casing, a fioat movable therein andadapted to follow the changing liquid level in the boiler, electricalheating elements carried by the float, a Circuit therefor, a controlswitch in said Circuit normally movable to open position,

a looking means therefor for holding the switch closed under normalboiler conditions and means for controlling the operation of the saidlooking means for preventing operability thereof under abnormal boilerconditions, the said means including provisions arranged within thecasing and Controlled by tlie position of the said float.

21. In an electric boiler` a boiler casing, a float movable therein a'ndadapted to follow the changing liquid level in the boiler, electricalheating elements carried by the float, a Circuit therefor, a controlswitch in said Circuit normally movable to open position, a lookingmeans therefor for holding the switch closed undernormal boilerConditions and means for controlling the operation of the said lookingmeans for preventing operability thereof under abnormal boilerconditions, the said means including a solenoid for actuating thelooking means and a. cut-out switch arranged within the casing andmovable Ito open and closed position b movement of the said float.

22. n an electric boiler, a boiler casing, a float movable therein andadapted to follow the changing liquid level in the boiler, heatingrelements carried by the float and means for `rectilinearly guiding thefloat in its movement responsive to the changing liquid level in theboiler.

23. In an electric boiler, a boiler closure, guiding means carriedthereby, a fioat guidedly movable on said guiding means and heatingrelements carried by the float.

24. In an electric boiler, a. boiler closure, a guiding means carriedthereby and located Centrally thereof` a hollow metallic float guidedlymovable on said guiding means and a plurality of electrical heatingtubes carried by the float for movement therewith.

25. In an electric boiler.v a boiler' casing, a plurality of electricalheating elements floatingly movable within the casing, an electricCircuit therefor and provisiolns for controlling the said Circuit to theheating elements controlled by the movement of the same.

26. In an electric boiler, a boiler casing, a float movable therein andadapted to follow the changing liquid level in the said boiler,

floatable heating elements associated with v the float, an electricalCircuit therefor and provisions for controlling the said Circuit to theheating elements controlled by the movement of the float. 27. In anelectric boiler, a boiler casing, floatable heating elements therein andmeans fo]l guiding the said heating elements for following the changingliquid'level in the boiler.

28. In an' electric boiler, a boiler Cas'ng, floatable electricalheating elements ther in, an electric Circuit therefor and meanscontrolled by movement of the said floating heating elements forControlling the operability of the said ,circuit.

` Siwgned at New York city, in the County of l\ew York and State of NewYork, this 3rd day of March, A. D. 1922.

' HYMAN E. COHEN.

